Rotocraft

ABSTRACT

An aerial vehicle includes independently controlled horizontal thrusters and vertical lifters to provide design and operational simplicity while allowing precision flying with six degrees of freedom and use of mounted devices such as tools, sensors, and instruments. Each horizontal thruster and vertical lifter can be mounted as constant-pitch, fixed-axis rotors while still allowing for precise control of yaw, pitch, roll, horizontal movement, and vertical elevation. Gyroscopes and inclinometers can be used to further enhance flying precision. A controller manages thrust applied the horizontal thrusters and vertical lifters to compensate for forces and torques generated by the use of tools and other devices mounted to the aerial vehicle.

BACKGROUND

Conventional rotorcraft, such as helicopters, are difficult to build,operate, and maintain. Training helicopter pilots requires substantialtime and effort. Helicopter controls typically include a cyclic pitchcontrol, a collective pitch control, anti-torque pedals, and a throttle.The cyclic pitch control is used to change the pitch of the rotor bladesin order to change the horizontal flying direction of the helicopter. Itshould be noted that a typical helicopter uses the same rotor (i.e., themain rotor) for both vertical elevation and horizontal motion. Ahelicopter can be propelled forward by tilting the rotor disk, but thisalso affects vertical elevation. Such coupling substantially complicatesflight controls. The collective pitch control is used to change theangle of all rotor blades collectively in order to change verticalelevation of the helicopter. The anti-torque pedals are used to controlthe direction in which the nose of the helicopter is pointed. The pedalsare generally used to change force output of an anti-torquing device,such as a fantail. The throttle is used to control power output of themain engine, which may change the rotational speed of the main rotor andimpact both vertical elevation and horizontal movement.

Such flight control complexity makes operation and maintenance ofrotorcraft an ongoing challenge. Yet, most rotorcraft still lack theability to make precise aerial maneuvers and can not be relied upon tooperate in confined spaces. Further, rotorcraft are generally notcapable of performing operations that exert forces on other objects.

Consequently, the techniques and mechanisms of the present inventionprovide a more easily maintained and operated aerial vehicle that canmaneuver in confined spaces and/or can use mounted devices such asmechanical tools, sensors, and instruments.

SUMMARY

An aerial vehicle includes independently controlled horizontal thrustersand vertical lifters to provide design and operational simplicity whileallowing precision flying with six degrees of freedom and using mounteddevices such as mechanical tools, sensors, and instruments. Eachhorizontal thruster and vertical lifter can be mounted asconstant-pitch, fixed-axis rotors while still allowing for precisecontrol of yaw, pitch, roll, horizontal movement, and verticalelevation. Gyroscopes and inclinometers can be used to further enhanceflying precision. A controller manages thrust applied by the horizontalthrusters and vertical lifters to compensate for forces and torquesgenerated by the use of tools and other devices mounted on the aerialvehicle.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates an example of an aerial vehicle in accordance withcertain embodiments.

FIG. 2 illustrates an example of a control system including an aerialvehicle controller and an external module in accordance with certainembodiments.

FIG. 3 illustrates a process of controlling an aerial vehicle inaccordance with certain embodiments.

FIG. 4A illustrates a side and a front view of an aerial vehicle with amechanical claw in accordance with certain embodiments.

FIG. 4B illustrates different stages during a door knob openingoperation in accordance with one embodiment.

FIG. 4C illustrates different stages during a door knob openingoperation in accordance with another embodiment.

DETAILED DESCRIPTION OF EXAMPLE EMBODIMENTS

In the following description, numerous specific details are set forth inorder to provide a thorough understanding of the present invention. Thepresent invention may be practiced without some or all of these specificdetails. In other instances, well known process operations have not beendescribed in detail to not unnecessarily obscure the present invention.While the invention will be described in conjunction with the specificembodiments, it will be understood that it is not intended to limit theinvention to the embodiments.

A rotorcraft or rotary wing aircraft is a heavier-than-air aerialvehicle that uses lift generated by its rotor blades revolving around amast. A mast is sometimes referred to as a shaft. A rotor includes amast and multiple rotor blades (typically between two and six blades)mounted to the mast. A rotorcraft can use one or more rotors to providevertical lift and/or horizontal thrust. Rotors on vertical masts andother vertical force generating devices are referred to herein asvertical lifters. Rotors on horizontal masts and other horizontal forcegenerating devices are referred to herein as horizontal thrusters.Vertical lifters and/or horizontal thrusters may include rotors,turbines, rockets, and/or static lifting surfaces.

Examples of rotorcraft include helicopters, autogyros, and gyrodynes.Helicopters typically have a main rotor along with an anti-torquedevice, such as a tail rotor or a fantail. As mentioned above,helicopter controls are complex. An autogyro utilizes an unpowered rotordriven by aerodynamic forces to develop vertical lift and a poweredpropeller or a turbine to provide horizontal thrust. The unpowered rotorrotates by air flowing up and through the rotor disk. The air rotatesthe rotor and generates vertical lift. Another example of a rotorcraft,a gyrodyne, has a main powered rotor for takeoff and landing.Anti-torque and horizontal propulsion are provided by one or more otherpropellers providing horizontal thrust. As power to the horizontalthrust propellers is increased, less power is provided through the mainrotor. At cruise speeds most or all of the thrust being provided by thepropellers. The main rotor receives power only sufficient to overcomethe profile drag and maintain some lift.

In certain embodiments, an aerial vehicle has two or more verticallifters. When two vertical lifters are rotors, these rotors may bearranged in tandem (one rotor in front of the other), transversely (sideby side), or coaxially (one rotor disc above the other, with concentricdrive shafts). When three of more vertical lifters are used, they may bepositioned at the corners of the aerial vehicle to provide bettercontrol of pitch and roll. In particular embodiments with at least tworotors, the rotor blades may intermesh, i.e., the rotor discs may passthrough each other, where the blades are synchronized so that theyintermesh without touching each other.

Complex controls used on some aerial vehicles are difficult to automateor operate. Further, using various devices mounted on an aerial vehiclewhile flying or hovering may be difficult or impossible.

A particular example of an aerial vehicle is an unmanned aerial vehicle(UAV). UAVs are used primarily for reconnaissance. Conventional UAVs aregenerally capable of aiming sensors during level flight or hovering.However, UAVs can not aim precisely during complex maneuvers, forexample, when pitch, roll, and yaw are changed simultaneously. Further,conventional UAVs are generally not capable of performing mechanicaloperations, such as opening doors, that may be particularly usefulduring indoor surveillance.

To overcome certain problems described above, a novel aerial vehicle isequipped with separate and independently controlled vertical lifters andhorizontal thrusters. In certain embodiments, hardware and controlfunctions are designated such that vertical elevation, horizontalmotion, yaw, pitch, and roll can be independently controlled. Thisallows precise flying without a need for complex flight controls. Inaddition, the independent control simplifies the task of keeping adevice (e.g., a tool, weapon, sensor) aligned with a target. Inparticular embodiments, the alignment of the tool or sensor may need amovement only within a single plane. An operator (e.g., an onboard orremote pilot, a tool operator) can manually adjust the device alignmentto keep the device on a target. Further, the independent controlfacilitates and simplifies automating certain flight control and tooloperation functions. Certain hardware and control aspects are describedin the context of FIGS. 1 and 2 respectively.

Independent control of vertical lift and horizontal thrust allows highmaneuverability and ease of control. Further, moving parts of verticallifters and horizontal thrusters may be protected such that an aerialvehicle may fly in confined spaces and contact and manipulate otherobjects. In certain embodiments, an aerial vehicle is configured to usetools, weapons, and sensors. Examples of sensors include electromagneticspectrum sensors (e.g., visual spectrum, infrared or near infraredcameras, radar systems, microwave and ultraviolet spectrum sensors),biological sensors (e.g., for detecting the airborne presence of variousmicroorganisms and other biological factors), chemical sensors (e.g.,laser spectroscopy), and other types of sensors.

Other functions of the aerial vehicle may include ability to enter andexit through windows, negotiate stairs, and operate a mechanical claw orother tools. For example, an aerial vehicle may include gyroscopic andrange sensors to control flight stability and adjust position relativeto a target while the vehicle performs complex maneuvers. Some of thesefunctions may be automated. Further, independent control of horizontalthrusters and vertical lifters allows use of fixed pitch rotors.Vertical control including elevation and horizontal stability (e.g.,pitch and roll angles) may be achieved by varying power output of thevertical lifters. For example, if vertical lifters are rotor-based, therotational speed of each lifter may be independently controlled. A fixedpitch design has fewer moving parts and simplifies control andmaintenance.

In certain embodiments, vertical lifters are not movable or pivotableand can only provide forces along the same constant axis. For example,if vertical lifters are rotor based, the shafts of these rotors arefixed and can not tilt like a shaft in a conventional helicopter. Inparticular embodiments, the axes for two or more vertical lifters aresubstantially parallel. Vertical lifters along with horizontal thrustersmay be fixed to a rigid frame.

A closed loop feedback control system may be used to collect informationabout changes in attitude, roll, pitch, and yaw, and to control verticallifters and horizontal thrusters. In certain embodiments, the controlsystem may be used for automatic control of certain flight functions,e.g., providing horizontal and/or vertical stability or maintaining aset distance to target objects. Other functions may be controlled by anoperator using a communication system. Feedback information may beprovided by various sensors, such as inclinometers, cameras, and/orgyroscopes. Sensor output may be used to adjust vertical lift orhorizontal thrust forces.

In certain embodiments further described below, an aerial vehicleincludes four fixed vertical lifters and two fixed horizontal thrusters.Four rotor based vertical lifters may be configured in such as a waythat two rotors may rotate in one direction and the other two may rotatein the other direction to compensate for torque created by the rotors.In particular embodiments, horizontal thrusters are used to compensatefor the torque generated by the vertical rotors.

According to various embodiments, an aerial vehicle is equipped withvertical and/or horizontal rangefinders (e.g., proximity sensors) todetermine a position of the aerial vehicle relative to nearby objects.Output of these range finders may be used to automatically controlposition of the aerial vehicle. These automated adjustments help tomaintain the aerial vehicle stability in demanding conditions. Inparticular examples, an operator sets an automated flying position byproviding vehicle coordinates and/or orientation relative to otherobjects. Automating some flying control function helps the operator tofocus on other functions, such as operating a mechanical tool orinstrument mounted on the aerial vehicle.

In certain embodiments, horizontal thrusters are capable of providinghorizontal thrust forces in both directions along the thrust axis (i.e.,pull and push the aerial vehicle). For example, an aerial vehicle may beturned faster if two substantially parallel horizontal thrusters providethrust forces in opposite directions.

Moving parts of vertical lifters and/or horizontal thrusters (e.g.,rotor blades) may be protected by shields to allow the aerial vehicle tocome in contact with objects without losing control or damaging itscomponents. For example, a circular cylinder-like shield or awire-shield may be used around the blades without substantiallyinterfering interferences with air flow created by the blades.

Various aerial vehicle structural and functional features will now bedescribed in reference to the figures. FIG. 1 is a schematicrepresentation of an aerial vehicle 100 in accordance with certainembodiments. An aerial vehicle 100 may include a frame 102, one or morevertical lifters 104, and/or one or more horizontal thrusters 106. Thevertical lifters and the horizontal lifters can be attached to ormounted on the frame 102. Other elements of the aerial vehicle mayinclude a device 108 attached to the frame 102. The device may beconfigured to move at least a portion of the device relative to theframe, e.g., a mechanical claw. In other embodiments, all parts of thedevice are stationary, e.g., a sensor. An aerial vehicle may be equippedwith a controller (not shown) configured to control the horizontalthrusters, the vertical lifters, and/or the one or more devices mountedto the aerial vehicle.

A frame 102 may be a rigid structure made out of light weight materials,such as aluminum, plastic, and composite materials. The frame 102 may beused to support other components of the aerial vehicle, such asthrusters, lifters, tools, and/or sensors. In the context of thisdocument, the frame 102 is sometimes used as a point of reference formotion of various components (e.g., movement of at least a portion ofthe tool relative to the frame).

Vertical lifters 104, which sometimes are also referred to as verticalthrusters, are used to provide vertical lift force, at least in thedirection that is opposite to the gravitation force. Generally, thecombined force output of all vertical lifters should exceed the weightof the aerial vehicle. Vertical lifters 104 may also be used generatevertical forces in the direction of the gravitational force (i.e., pushthe vehicle down). This feature may be used to overcome torque exertedby the device (e.g., opening a door knob) and/or to press down on anobject. It should be noted that vertical lifters 104 may also generatesome horizontal thrust force, e.g., when a lifter or an entire vehicleis tilted or when a rudder is used.

A number of vertical lifters is determined based on a force output ofeach lifter, weight of the aerial vehicle, simplicity of control,maneuverability requirements, and other considerations. In particularembodiments, an aerial vehicle 100 has one vertical lifter 104, whichmay be coupled with one or more horizontal thrusters 106 or used withoutany horizontal thrusters at all. If no horizontal thrusters are used,then horizontal forces may be provided by using a rudder, pivoting thevertical lifter itself, and/or positioning vertical lifters at an anglewith each other and controlling their force outputs. This design (with asingle vertical lifter) may be beneficial from weight perspective, butcontrol functions are complex and maneuverability is limited. In certainembodiments, an aerial vehicle has at least two vertical lifters. In thesame or other embodiments, an aerial vehicle has at least one verticallifter and at least one horizontal thruster. Such embodiments may bemore suitable when an aerial vehicle needs to deliver some torque toexternal objects.

Higher maneuverability may be achieved by using additional lifters andthrusters. In certain embodiments, an aerial vehicle has four verticallifters and two horizontal thrusters that are mounted to the framewithout pivoting capabilities. Flying control is performed primarily byadjusting forces delivered by each thruster and lifter. In particularembodiments, forces delivered by vertical lifters are parallel to eachother. In the same or other embodiments, forces delivered by horizontalthrusters are parallel to each other. Further, the vertical control(e.g., altitude changes, pitch, and roll) of the aerial vehicle may beprovided by adjusting forces delivered by the vertical lifters, whilethe horizontal controls (e.g., forward and backward motions and yaw) maybe provided by adjusting forces delivered by the horizontal thrusters.In certain specific embodiments, one or both horizontal thrusters arecapable of providing forces in two directions. In certain specificembodiments, up to four horizontal thrusters are capable of providingforces in four directions, allowing lateral movements as well as forwardand backward movements and yaw.

In certain embodiments, vertical lifters and horizontal thrusters do notpivot relative to the frame and/or do not have corresponding rudders.Therefore, flight controls are performed by adjusting forces of thelifters and thrusters. In other embodiments, one or more verticallifters and/or horizontal thrusters pivot relative to the frame toprovide additional control flexibility. In the same or otherembodiments, one or more vertical lifters and/or horizontal thrustershave one or more corresponding rudders. Pivoting may be performed basedon output provided from the controller as further described in thecontext of FIG. 2. Further, the controller may be used to change forcesdelivered by vertical lifters and horizontal thrusters. In particularembodiments, one or more horizontal thrusters include shafts configuredto change rotating speeds and rotating directions based on inputsprovided by the controller.

Vertical lifters and/or horizontal thrusters may be of many types, suchas fixed pitch propellers, turbines, rockets, compressed air devices,etc. Examples of power sources for vertical lifters and/or horizontalthrusters having a propeller configuration include an electrical motorand a combustion engine. Typically, each lifter and thruster has its owndesignated power source, which may be controlled independently to changeforce provided by each lifter and thruster. However, in particularembodiments, an aerial vehicle may have a power source and a powertransmission delivering power from the power source to two or morelifters and/or thrusters, such that two or more lifters and/or thrusterscan deliver variable (relative to each other) forces (e.g., speeds inpropeller configuration embodiments).

In certain embodiments, a controller may engage vertical lifters and/orhorizontal thrusters to reduce the effect of recoil forces generated bya tool or weapon, either manually or automatically (e.g., by a set ofpre-programmed instructions). For example, an aerial vehicle may adjustforce outputs of certain lifters and/or thrusters together withinitiating an action with a tool or weapon. In certain embodiments, anaerial vehicle is moved from its predetermined position prior to thetool or weapon exerting any force on the aerial vehicle in order tominimize the overall amplitude of the deviation from the predeterminedposition when the force is generated. This option may be used for forcesthat are high in magnitude but short in duration, such as punching arivet or firing a bullet.

In certain embodiments, vertical lifters and/or horizontal thrusters maybe used to apply force on external objects through a tool, a frame, orother components of the vehicle. For example, an aerial vehicle may beused for pushing objects (e.g., opening a door, moving a box), insertingor pushing a wedge, breaking through the objects (e.g., windows, walls,doors), and exerting forces to perform other functions. Further, a toolmay be used to open and close doors and windows, apply sensors toobjects, establish electrical connection with power sources, and performother functions. Particular embodiments of an aerial vehicle used toopen door knobs are described in the context of FIGS. 4A-4C. In certainembodiments, vertical lifters and/or horizontal thrusters mayadditionally be used during application of external forces to stabilizethe vehicle (e.g., maintaining it horizontally stable or compensatingfor reactive forces or torques exerted by objects onto which forces ortorques have been applied).

Returning to FIG. 1, in certain embodiments, an aerial vehicle includesone or more devices 108 that may be mechanical tools (e.g., a mechanicalclaw, a punch), sensors (e.g., temperature sensor, proximity sensor,video camera, laser scanner, etc), and/or weapons (e.g., a gun, anexplosive charge, a missile). The device 108 may be attached to theframe 102. A portion of the device 108 may be movable relative to theframe 102. In certain embodiments, the motion of the device 108 relativeto the frame 102 is capable of exerting a force adequate for usefulwork. Additional details of device are described in the context of theFIG. 2 and FIGS. 4A-4C.

FIG. 2 illustrates a control system 200 in accordance with certainembodiments. A control system 200 includes an aerial vehicle controller202 positioned on the vehicle. For example, the controller 202 may beattached to the frame. In certain embodiments, the control system 200also includes an external module 204 that communicates with the vehiclecontroller 202. The overall system 200 is configured to transmit databetween the aerial vehicle controller 202 and the external module 204,such as data related to flight control and device operation, datacollected by sensors, and other forms of data.

An aerial vehicle controller 202 may include one or more input modules,such as a communication interface 222, a user interface 224 (includingvarious user input and output features), and one or more sensors 226.The communication interface 222 may be any device capable ofestablishing wireless communication with the external module 204 (or anyother external communication device) and transmitting data between thecontroller 202 and the module 204. In particular embodiments, thecommunication interface 202 is a radio transmitter. Each controlfunction of the aerial vehicle (e.g., a force output of each thrusterand lifter, a device control, sensors outputs) may have a dedicatedradio channel. Radio transmission may be performed in FM-frequency rangeand modulated with a pulse position modulation or a pulse codemodulation technique. Furthermore, spread spectrum based on frequencyhopping in the 2.4 GHz band or other frequency bands may be used forcommunication.

A user interface 224 may be provided on the controller 202 to allow fordirect input of data by a user/pilot (e.g., programming a new flightpath or controlling a manned vehicle during the flight). Examples ofuser interfaces include displays (e.g., touch screens), keyboards,joysticks, levers, and pedals. Furthermore, the controller 202 mayinclude one or more communication links, such as serial ports. Accordingto various embodiments, an aerial vehicle is an unmanned aerial vehiclethat has a controller 202 to receive, process, store, transmit, andgenerate various flight control and device operation instructions.

A controller 202 may include one or more sensors 226 for gatheringinformation around the aerial vehicle. Examples of the sensors include avideo camera, a proximity sensor, an inclinometer, a gyroscope, atemperature sensor, a positioning system (e.g., a satellite based globalpositioning system, a radio/cell phone based triangulation system), etc.For example, an inclinometer or a gyroscope may generate informationused for horizontal alignment of the aerial vehicle. Sensor informationmay be used by the controller 202 to send instructions to the verticallifters and/or horizontal thrusters to adjust their force outputs. Incertain embodiments, a gyroscope is configured to automatically controlvertical lifters to continuously maintain stability.

Furthermore, a controller 202 may include a power unit 216 that isshared with other components of the aerial vehicle, such as verticallifters or horizontal thrusters. A power unit 216 may include an energycarrying device (e.g., a battery, a capacitor) or a generating device(e.g., a generator). The power unit 216 may also include a charger forcharging the energy carrying device. According to various embodiments,the aerial vehicle includes an electrical plug or electrical wires thatcan be plugged into an electrical outlet during remote operation. Inparticular embodiments, the electrical plug or electrical wires can beinserted into an electrical outlet during the mission, e.g., while theaerial vehicle is used to survey a building interior.

The controller 202 may also include a processor 218 and a memory 220.Examples of tangible computer memory types include a hard-drive, a flashmemory, a recorded disk, and other tangible memory storage devices. Thememory 220 may be used to store a set of instructions for controllingvehicle operations. The processor 218 may be configured to process andexecute these instructions.

An aerial vehicle controller 202 may also include one or more outputdevices, such as a vertical lifter controller 210, a horizontal thrustercontroller 212, and a vehicle device controller 214. Further, inembodiments where a thruster or a lifter is pivotable or has acorresponding rudder, an output device may be used to control some orall functions associated with pivoting the lifter, thruster, and/orrudder.

In certain embodiments, flight control functions of an aerial vehiclecan be fully automated and require no ongoing input from a pilot eitheron board the vehicle through an external module. An automated flightcontrol may use inputs from sensors, maps, pre-loaded information, etc.Generally, automated controls are more suitable when flight paths areknown. For example, a map of an open space or a building may used fornavigation. Various sensors may also be used to assist with certainnavigation functions (e.g., avoiding collisions with objects on theflying path and maintaining distance from objects).

In particular embodiments, a part of navigation is performed manually(e.g., by a pilot on the ground controlling the vehicle through theexternal module). For example, a pilot may remotely guide the vehicle toa target inside a building relying on video images provided by thevehicle's video cameras and transmitted to the external module for thepilot to view. During this guiding process, the vehicle controller maycontinuously record its flying coordinates. In other words, the vehiclecontroller constructs a map of its flying path. This map may be laterused by this or other vehicles, for example, to exit using an automaticflying mode (with little or no assistance from a pilot). This featuremay be particularly useful in situations when fast exit from enclosedspaces is required, such as rescue or assault operations.

According to various embodiments, some flying control functions areautomated, while other flying control functions are performed by a pilot(e.g., remotely through the external control module). For example, anaerial vehicle may use gyroscope data to automatically maintainhorizontal stability while other flight motions are performed manually.In another example, automated control is used to maintain a stableposition of the vehicle relative to the target (e.g., a stable hoveringposition), while a pilot operates a tool, sensor, and/or weapon. Inparticular embodiments, the controller provides input to horizontalthrusters and/or vertical lifters based on feedback from sensors inorder to maintain constant roll, pitch and yaw, while the device isremotely controlled by a pilot (or an operator) based on informationprovided by sensors (e.g., a video camera directed at the target).

Generally, an aerial vehicle is remotely flown by a pilot through anexternal module, while the vehicle controller is used to ensure certainflight functions (e.g., horizontal stability, elevation, distance fromsurrounding objects) based on sensor feedback. In certain embodiments,most or even all flight control functions are performed remotely by apilot. It should be noted that when certain control functions areautomated, the automation process may be implemented at an aerialvehicle controller 202, an external module 204, or some other computersystem (not shown in FIG. 2).

According to various embodiments, an external module 204 of the controlsystem 200 sends control commands to and receives responses from theaerial vehicle. The external module 204 may include a modulecommunication interface 230 for exchanging data with the vehiclecommunication interface 222. In particular embodiments, the externalmodule has a module processor 232 and module memory 234. The externalmodule 204 may also include a module user interface 236, which may allowcontrol personnel to receive output and provide input. Examples of userinterfaces include displays (including touch screens), keyboards,joysticks, levers, and pedals. The external module 204 may also includeone or more communication links, such as serial ports.

Certain features of aerial vehicles are best illustrated by describingoperations of the vehicle. FIG. 3 illustrates an example where an aerialvehicle is used for indoor surveillance in accordance with certainembodiments. The process 300 may start with preparing an aerial vehiclefor a mission (block 302), which may involve charging a vehicle powerunit (e.g., charging battery and/or filling with fuel), installingmodular equipment on the aerial vehicle (e.g., attaching another tool,sensor, or weapon to the frame), and uploading a set of instructions tothe memory of the aerial vehicle controller. Some of these operations(e.g., uploading instructions) may continue throughout the entireprocess 300.

When a vehicle is ready for a mission, it may be guided to the firsttarget, which may involve performing a series of operations 310. Some orall data used for guidance of the aerial vehicle may be provided byvehicle's sensors (block 304). In certain embodiments, the data is alsotransmitted to the external module. Further, a vehicle may be guidedusing instructions entered by an operator/pilot on the user interface ofthe external module. These instructions are then received by the aerialvehicle over a wireless communication interface (block 306). At somepoint in this operation, instructions may be processed by the processorof the external module and may be stored in the memory of the externalmodule. Furthermore, the instructions may come to the external modulefrom a remote computer system through some network interface, instead ofbeing input by an operator.

In certain embodiments, the control of the vehicle is performed entirelyby the aerial vehicle controller without receiving any flight controlexternal instructions (i.e., process 300 does not include operation306). The external module may be used solely to receive information fromthe vehicle or not used at all. Autonomous operation of the aerialvehicle may be needed in areas where communication with external modulesmay be difficult to establish (e.g., flying close to or inside metalstructures, power lines, or bulk liquids that tend to interfere withradio communication). An aerial vehicle may guide itself to the targetbased on the preloaded instructions and sensor data (provided inoperation 306). In a particular embodiment, a pilot onboard of theaerial vehicle guides the vehicle to its target (group 310) and/oroperates a device at a target (group 320) with or without sensor dataand wirelessly received instructions.

Sensor data (from operation 304) and/or instructions (from operation306) may be used to independently control power levels applied to eachvertical lifter and horizontal thruster in order to control the flyingpath of the aerial vehicle (operation 308). A vehicle may continuouslyreceive new sensor data and/or new instructions for further guidance. Inparticular embodiments, one or more operations in group 310 arerepeated.

An aerial vehicle may transmit certain data collected by its sensors(e.g., video images from the video camera) to the external module.According to various embodiments, the data is presented on the userinterface and used by an operator/pilot to generate a set of flightcontrol and device operation instructions (e.g., based on received videoimages) that are transmitted back to the aerial vehicle in operations306 and 316.

Once an aerial vehicle reaches the target, it may perform one or moreoperations directed at the target (group 320). For example, an aerialvehicle may take video or still images of the target, measuretemperature and other characteristics of the target, and/or performmechanical actions on the target. In certain embodiments, an aerialvehicle receives data collected from sensors (block 314) and/or receivesinstructions over a wireless interface (block 316) that are used forcontrolling a device, such as a mechanical tool, a sensors, or aninstrument or weapon, during its operation (block 318). In certainembodiments, the data is also transmitted to the external module.

Some operations in groups 310 and 320 may be repeated to guide an aerialvehicle to another target and perform operation on that target. Further,in certain embodiments, operations in groups 310 and 320 are performedsimultaneously. Certain flight control functions need to be performed inorder to maintain the aerial vehicle at a desired position relative tothe target. For example, vertical lifters and horizontal thrusters maybe controlled to counterbalance force and/or torque exerted by thevehicle's device on the target.

In particular examples, an operation may involve opening a door, awindow, or another obstacle with a latch or a lock. For example, duringinterior surveillance an aerial vehicle may encounter a closed door.Opening a door may require rotating or turning the door knob or doorhandle. An aerial vehicle may be configured to perform these operationswith its mounted devices (e.g., mechanical tools, sensors, and/orweapons). Knob turning capabilities will now be explained in moredetails in the context of FIGS. 4A-4C. It should be noted that incertain embodiments, an aerial vehicle is equipped with a device thatcan be used to break through an obstacle instead of or in addition toopening it. Examples of such devices include various forms of weapons,e.g., a shotgun, an explosive charge.

FIG. 4A illustrates schematic side and front views of an aerial vehicle402 with a mechanical claw 404 in accordance with certain embodiments.The claw is shown with three mechanical fingers 410, 412, and 414. Atleast one of the mechanical fingers is movable in order to providepressure on an object in the claw. Alternatively, the vehicle itself canbe thrust against an object to provide necessary pressure (e.g., topress on a door handle). FIG. 4B illustrates schematic front views ofdifferent stages during door knob opening in accordance with oneembodiment. An aerial vehicle and/or a mechanical claw, if it ismovable, can be moved into a position such that the mechanical fingers410, 412, and 414 of the claw are positioned around the door knob 416.One or more fingers are then moved such that some or all fingersestablish contact with the knob 416. Generally, certain pressure isprovided between the fingers and the door knob. The amount of pressuredepends on friction between the door knob and the fingers, torquerequired to turn the knob, and other factors.

It should be understood that the claw can have two, three, four, or anyother greater number of mechanical fingers. For example, even themechanical claw with two mechanical fingers may be capable of rotatingthe knob (establishing enough friction between the knob and themechanical fingers to transfer the torque) if a contact of each of twomechanical fingers is sufficiently large. A three finger design may beeasy to control to grab round objects, such as door knobs. However, fouror more mechanical fingers may provide better torque transfercharacteristics.

Once the mechanical fingers establish the contact with the knob 316, theclaw may start rotating in order to unlatch the door. In certainembodiments, the claw rotates relative to the frame, while the positionof the aerial vehicle is maintained. In other embodiments, the aerialvehicle itself rotates to provide a part or a full door knob rotationrequired for unlatching. Once the door knob unlatches, the aerialvehicle pulls or pushes the door using a motion of the mechanical clawor that of the entire apparatus. It should be noted that during theentire process, vertical lifters and/or horizontal thrusters may be usedto stabilize and move, when necessary, the aerial vehicle with respectto the door knob.

FIG. 4C illustrates different stages during door knob opening inaccordance with other embodiments. In these embodiments, the mechanicalfingers 420, 422, and 424 of the mechanical claw include rollers 421,423, and 425 that establish contact with the door knob 426. The rollers421, 423, and 425 are configured to rotate relative to the mechanicalfingers 420, 422, and 424, and at least one of the rollers is configuredto exert torque onto the knob 426 to turn the knob. In thisconfiguration, the mechanical claw and the mechanical fingers 420, 422,and 424 may remain stationary while the door knob 426 rotates.

In certain embodiments, an aerial vehicle may enter and exit throughwindows and other breakable surfaces by breaking through the surfacewith its own body (e.g., a part of the frame), a spring loaded orpneumatic punch, or an explosive device. For example, a vehicle mayorient itself towards a surface with the part or device that is used forbreaking this surface. In case of breaking with vehicle's own body, avehicle may accelerate towards the surface. A speed at the point ofcontact with the surface depends on vehicle's weight and properties ofthe surface (e.g., materials, thicknesses, reinforcements).

In certain embodiments, an aerial vehicle is equipped with one or moreof the following tools: a drill, a screwdriver, and a wrench. Thesetools as well as mechanical claw and other tools may rely oncountervailing forces and/or torques generated by the vehicle to exertforces and/or torques on external objects. An aerial vehicle equippedwith various tools may be used for maintenance of structures, indoor oroutdoor.

Although the foregoing invention has been described in some detail forpurposes of clarity of understanding, it will be apparent that certainchanges and modifications may be practiced within the scope of theappended claims. It should be noted that there are many alternative waysof implementing the processes, systems and apparatus of the presentinvention. Accordingly, the present embodiments are to be considered asillustrative and not restrictive, and the invention is not to be limitedto the details given herein.

1. An aerial vehicle comprising: a frame; a plurality of horizontalthrusters attached to the frame; a plurality of vertical liftersattached to the frame; a device attached to the frame, wherein thedevice comprises one or more selected from the group consisting of amechanical tool, a sensor, and a weapon; and a controller attached tothe frame and configured to control the plurality of horizontalthrusters and/or the plurality of vertical lifters, wherein the aerialvehicle is capable of maneuvering in all directions and axes byindependently controlling the thrust applied by the plurality ofhorizontal thrusters and the plurality of vertical lifters.
 2. Theaerial vehicle of claim 1, wherein the aerial vehicle is capable ofchanging yaw, pitch, roll, or elevation independently from each otherwhile maintaining the device on a target with changing the orientationof the device within a single plane.
 3. The aerial vehicle of claim 1,wherein a portion of the device is configured to move relative to theframe.
 4. The aerial vehicle of claim 1, wherein the aerial vehicle isan unmanned aerial vehicle (UAV).
 5. The aerial vehicle of claim 1,wherein the aerial vehicle is configured to enter a building by openinga door and/or a window and/or ramming through the door and/or thewindow.
 6. The aerial vehicle of claim 1, wherein an external force isexerted by moving the device relative to the frame.
 7. The aerialvehicle of claim 1, wherein an external torque is exerted by moving thedevice relative to the frame.
 8. The aerial vehicle of claim 1, whereinthe plurality of vertical lifters comprises four independentlycontrolled vertical lifters, wherein the thrust applied by each of theindependently controlled vertical lifers is varied by changingrotational speeds associated with each of the independently controlledvertical lifters.
 9. The aerial vehicle of claim 1, wherein theplurality of horizontal thrusters comprises two independently controlledhorizontal thrusters, wherein the thrust applied by each of theindependently controlled horizontal thrusters is varied by changingrotational speeds associated with each of the independently controlledhorizontal thrusters.
 12. The aerial vehicle of claim 9, furthercomprising a battery, wherein the aerial vehicle is configured toestablish an electrical connection with a stationary external powersource to recharge the battery while the aerial vehicle is remotelyoperated.
 13. The aerial vehicle of claim 12, wherein the stationaryexternal power source is a wall-mounted electrical outlet.
 14. Theaerial vehicle of claim 1 further comprising a gyroscope for controllingthe plurality of vertical lifters.
 15. The aerial vehicle of claim 1,wherein an output from the proximity sensor is used by one or morevertical lifters from the plurality of vertical lifters and/or one ormore horizontal thrusters from the plurality of horizontal thrusters tomaintain substantially constant distance from an external objectdetected by the proximity sensors.
 16. The aerial vehicle of claim 1,wherein the device comprises a mechanical claw.
 17. The aerial vehicleof claim 16, wherein the mechanical claw is configured to turn a doorknob.
 18. The aerial vehicle of claim 17, wherein the mechanical clawcomprises a plurality of mechanical fingers and at least one mechanicalfinger is movable.
 19. The aerial vehicle of claim 18, wherein at leastone mechanical finger in the plurality comprises a roller.
 20. Theaerial vehicle of claim 16, wherein the mechanical claw is configured tomove in and out relative to the frame and to turn relative to the frame.21. The aerial vehicle of claim 20, wherein the controller is configuredto control one or more of the plurality of vertical lifters and one ormore of the plurality of horizontal thrusters to counterbalance forcesand torques exerted in the aerial vehicles during operation of themechanical claw, sensor, or weapon.
 22. A method, comprising: receivingdata collected from sensors mounted to a frame of an unmanned aerialvehicle, the unmanned aerial vehicle having a plurality of verticallifters and a plurality of horizontal thrusters; receiving instructionsover a wireless interface to operate a mechanical tool connected to theframe; and independently controlling power levels applied to each of theplurality of vertical lifters and each of the plurality of horizontalthrusters to compensate for feedback resulting from operating themechanical tool.
 23. A method, comprising: receiving data collected fromsensors mounted to a frame of an unmanned aerial vehicle, the unmannedaerial vehicle having a plurality of vertical lifters and a plurality ofhorizontal thrusters; receiving instructions over a wireless interfaceto guide the unmanned aerial vehicle; and combining the data collectedfrom the sensors and the instructions received over the wirelessinterface to independently control power levels applied to each of theplurality of vertical lifters and each of the plurality of horizontalthrusters to control a flying path of the vehicle.